Sendmail/smart host with


My internet service provider (ISP, Eniig) has announced that they will no longer provide a SMTP relay host (outgoing Simple Mail Transfer Protocol relay), and on top of that they earlier they stated that they will not setup reverse DNS on my fixed IP – so with these two (really bad) decisions in mind, I had to come up with a solution.

By the way – Eniigs reason for not providing SMTP relay servides anymore is that they apparently cannot manage to have such a server in production anymore because of SPAM anti measures etc. Really? An ISP not having the resources and knowledge to run a SMTP server in production anymore? Really!?!?!

Anyway – Eniig suggested using and even provides a free (almost unlimited) access until end of May 2018, so although there is a lot of cheaper alternatives out there – why not?
For non-Danish speakers wanting to join, also runs an international version of their service on

Only problem is that it requires SMTP to the submit port (587) and authentication. And it is a requirement for me to continue to use my FreeBSD/Sendmail box, which is providing a lot of services – including some rarely used SMTP-services – for family and friends. This is actually a non-profit/free setup – so it is a pita that Eniig actually are putting extra costs into this, without reducing the cost for the Internet connection. Shame on them!!!

Actually, it was not that big of a hassle to configure Sendmail for this purpose – and I’m also doing SMTP authentication, SpamAssassin filtering, procmail  and a lot of other stuff in my Sendmail :-).

This is what I had to do:

Create /etc/mail/authinfo with one line (terminate it with a line break): "U:root" "I:< login name>" "P:< password>" "M:LOGIN PLAIN"

…replacing values in < > with you accounts values from
I feel most secure by making this file rw for root only

Run makemap of this file to create a authinfo.db-file

makemap hash authinfo < authinfo

Correct your (whatever it is called on your system). Add these lines:

define(`RELAY_MAILER_ARGS', `TCP $h 587')dnl
FEATURE(`authinfo',`hash /etc/mail/authinfo')dnl

Note: You should change this for the sendmail queue runner process, not a SMTP submit service etc.

Compile your file into a file. This is easily done on FreeBSD 🙂

make cf

Restart sendmail. Again – this is easy on FreeBSD

make restart

Also: remember to correct your SPF and similar setups on your domains according to

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